Top weekend shows: Charlie Musselwhite, Zac Brown Band

gregkotWind is not kind to sound at the bog stages at either end of Grant Park. #lolla like a bad phone connection.

Charlie Musselwhite: The great blues harpist is coming off a 2010 release, “The Well” (Alligator), that ranks with his strongest work. In a career that dates to the hard-scrabble 1960s Chicago scene, Musselwhite shows no sign of slowing down, 8 p.m. Friday at Space, 1245 Chicago Av., $20 and $35; evanstonspace.com.